Subject: Molecular hydrogen knots in the Crab Nebula--New light on an old subject

We discovered 55 knots of molecular hydrogen in the Crab Nebula. What does this new component tell us? The H2 knots are associated with a cooler population of the well-known filaments, and strangely 80% are on the back side of the nebula. The temperature of the H2 emission is 2500-3000K. We have images and spectra from the SOAR Telescope and images from HST; we have new spectra from the Large Binocular Telescope.